If you have RO installed in your home RO is fine, most modern nutrients (flora series) will have enough (cal/nit) calcium nitrate in the base formulas, but with RO I would add a couple ml every 3rd watering, like others have said RO isnt necessary in soil especially if your paying for it? Im in Coco and DWC, I use Salt Nutrient (megacrop), with RO I add my nutrient and I know exactly whats in my water in elemental ppms at all times, I water to run-off which is basically a "flush and fill" each watering resetting the Rhizo with a fresh nutrient solution, I know whats in my media at all times pH/ppm/ec - I grew in soil for 20 years and grew bangers! but "never knew exactly" what was in my soil after a few weeks in Veg or several wks into flower? (the build up of nutrient salts) I cant stand the lack of control in Soil. Some of Us are just Control Freaks! lol In Engineering we call this "Process Control" if you dont have full measurable Control of the Process you're "Wingin It" and Wingin It will get you Fired! Measurable DATA must be collected! lol, Installing RO is a 30 min job now days....(in bold is just to answer your question) right on!
